As soon as the public gets information that a disaster is looming, people go into panic buying mode. Expect food, bottled water, camping supplies, bread, snacks, camp stoves, charcoal,,,,, well, if its on the shelf, expect people to buy it.
There is one thing that is sold out very quickly, and that is fuel. Before you know it the fuel lines are out to the street, and tempers start to flare.
This video was taken after hurricane Ike hit southeast Texas. People were blocking the roads so other traffic was not able to get through. I did not see any road rage, but its very possible it did happen.